Seat dressing tool



Dec. 17, V1946.

GJA. BARNES SEAT DRESSING TOOL Filed Oct.. 15., 19,45

Patented Dec. l?,` 1946 UNITED STATES PiISfIlEZNTk OFFICE 2,412,859V SEAT `DRESSING 'IQOL Galen A. Barnes, Indianapolis, Ind. Application October 15, 1945, Serial No. 622,295

(Cl. 51l31) 9 Claims. 1

This invention relates to a tool for dressing the seat of a shaft-seal, for example of the seal around the driving shaft of an automobile waterpump.

In water pumps commonly used on automobiles, and in many analogous situations, a shaft open` ing is sealed by a sealing disk rotatable with the shaft and yieldingly urged axially against an annular seat on the housing. The seat must be fiat, true, and perpendicular to the shaft axis, and must have a smooth surface. In a water pump, the seat is surrounded by other parts of the' housing, and its inaccessible location makes it extremely difcult to dress, save with expensive factory tools not practically availableV for repair work. In consequence, when such a seat is damaged, even though but slightly, it is practically necessary to discard the whole housing.

It is the object of this invention to provide a simple inexpensive tool lwhich will be practical for repairing such seal-seats.

In carrying out my invention, I provide a cylindrical head to be mounted for relatively high speed rotation on any available standard shaft, conveniently a standard half-inch 4electric-motor shaft. At its forward end the head carries 4an interchangeable tool which provides a dressing face perpendicular to its axis of rotation. An eccentric which rotatably Vfits a .bore in the pump case and which `is rotatable with respect to the head, is positioned by a pilot shaft with its axis of eccentricity coaxialwith the head axis. The eccentric will supporta housing with its seal-seat in proper position for dressing against the dressing face .of the tool; axial pleSSllre can be applied manually; and manual rotation .of the eccentric will carry the seal seat inan eccentric path over the face of the rotating tool, to give adequate relative movement to ensure effective dressing of the seat to the desired at,

true, and smooth condition.

The accompanying drawing illustrates my invention. In such drawing, Fig. 1 is an axial section through a typical shaft seal, shown in association with a water pump; Fig. 2 is an axial section showing a preferred form of my tool in position to dress the seat of the seal shown in Fig. 1; Fig. 3 is an end elevation of the tool shown in Fig. 2; and Fig. 4 is an axial section showing a modified embodimentfof my invention.

My tool is adapted to dress the seat of a shaftseal such as that of the water pump typified in Fig, 1. That water pump comprises .a case I formed to provide a rotor housing II, an inlet passage I2 and a shaft-bearing housing I3. The

Z. housing I3 has a shaft-bore I 5 and a larger bore I4 for the reception of a bearing I5. The rotor shaft `i'I is mounted in the bearing I5 and carries at its inner end a pump rotor I8. In common practice, the outer end of the shaft I1 carries a sheeve 20 for a driving belt, and may also Vcarry a fan. To seal the pump around the shaft Il, a sealing disk 2l carried by the rotor I8 and sealed with respect thereto by a bellows 29, is pressed by a spring 28 against a seat 2B on the shaft housing. Conveniently, the spring 23 lies around the bellows 2S), in a Acup 25 in the rotor. Lugs 3D on the sealing disk 2l engage notches 3i in the rotor it, to cause the disk 21 to turn with Vthe rotor it.

The seal seat 2B is formedas an annular at on a bess 32 projecting inwardly around the shaft l?, a plane normal to the. axis of the shaft `Z'I, and generally concentric with that axis.L It thus lies ncrrnal to, and concentric with, the shaftrbore tliiiand the bearing-bore I4.

For dressing the seat 26, the tool shown in Figs. 2 and`3 comprises a head '3.5 adapted to be mounted on a driving shaft 36, conveniently a standard one-half inch shaft of an electric motor or of an arbor. The rotor 35 is formed to provide a shoulder JI to receive an annular facing tool 38. This is desirably formed of metal and faced with a renewable abrasive disk 39. The facing tool 13` is conveniently replaceable, as by being held in place by a snap ring and provided with a hole 4I to engage a driving pin 4 2 on the rotor 35. A pilot .45 projects forwardly from the rotor 3,5 coaxial therewith, and is received in an eccentric sleeve 5) which rotatably ts a bore in the fhousing I9, Vco riveniently the bore I4 in that boss I3. ',Ihe sleeve 5I] is provided with a manually Operable handle 5I.

In use, the head 35 is mounted on a shaft 3B to rotate about a fixed axis. A facing tool 38 is placed on the head 35 against the shoulder 31, and a pump case IE! is then placed in the position shown in Fig. 2, with its seal-scat 26 against the abrasive face 39. The eccentric 5i] is then inserted in the bore Ill around the pilot 45, which xes the common axis of the head 35 and pilot 55 parallel to the bore I4 of the pump case III, and hence perpendicular to the seat 2S. With the casing Ill manually held against rotation and pressed axially, the head 35 is rotated at high speed, and the handle 5I is operated to rotate the eccentric to carry the casing in an eccentric orbital path about the axis of eccentricity of the eccentric 55. The working face 39 is thus rotated at dressing speed 3 against the seal-seat 26, while the seat 216 is translated through a circular path about the axis of rotation of the working face 39. This causes, between the seat 26 and the working face 39, a simultaneous rotation and relative movement in an eccentric path, to dress and true the seat 26.

When it is desired to change the working surface 39 during the course of the operation, the tool 38 may be removed by sliding it oli the end of the pilot 4-5 and replacing it with one which has a face 39 of the desired characteristics.

In the modification of Fig. 4, the pilot d5 is carried by the eccentric 59 instead of by the head 35, and the head 35 is bored to receive the no-w inwardly projecting end of the pilot 45; In this case, the tool 38 is provided with a rim 53 to engage a snap ring 5t carried circumferentially on the rotor 35.

Preferably, the tool is provided with a plurality of eccentrcs 50 having outer surfaces of different diameters, to adapt the tool to use on different casings. For a large majority of automobile water pump seals, because of standardization, one size of eccentric 5G will be suiicient, and eccentrics 5l) of two sizes will adapt the tool to substantiallir all of the water pumps now in use.

The tool of this invention is simple and inexpensive, so that it may readily have wide availability in repair shops. It will effectively dress and true the seats of water pump casings. It thus makes it possible to continue in service many water pump casings which under the present practice must be destroyed.

Iclaim as my invention:

' 1. A device for dressing an annular shaft-seal seat surrounding the shaft bore of a water-pump case and concentric with said bore and with the coaxial bearing-receiving bore of said case, comprising a head rotatable at dressing speed on a xed axis, an annular tool thereon providing a radial work-surface, a pilot coaxial therewith, an eccentric positioned by said pilot with its axis of eccentricity coaxial with said head, said eccentric having an outer cylindrical surface rotatably tting said bearing receiving bore to support said pump case with its shaft-seal seat against said work-surface inposition to be dressed true, and a crank on said eccentric whereby it may be rotated in said bearing-,receiving bore to carry the axis thereof and the center of said seat over an eccentric path of revolution about the axis of rotation of said tool and head.

2. A seat-dressing tool as defined in claim 1 in which the pilot is integral with the head and is rotatably received in said eccentric.

3. A seat-dressing tool as defined in claim 1 in which the pilot is integra1 with the eccentric and is rotatably received in said head.

4.' A device for dressing an annular seat on a housing perpendicular -to and generally concentric with a bore in said housing, comprising a head rotatable at dressing speed, an annular tool thereon providing a Work-surface perpendicular to the axis of head rotation, a pilot coaxial therewith, an eccentric having a cylindrical outer surface adapted to rotatably t said bore, and a handle for rotating said eccentric to cause relative revolution between the bore axis and the common axis of the pilot, head, and tool.

`5.11151 seat-dressing tool as dened in claim 4in which the pilot is integral with the head and is rotatably received in said eccentric.

6. A seat-dressing tool as defined in claim 4 in which the pilot is integral with the eccentric and is rotatably received in said head.

7. A device for dressing an annular seat on a housing perpendicular to and generally concentric with a bore in said housing, comprising a head rotatable about a iixed axis, a shoulder on said rotor, a pilot extending beyond said shoulder and coaxial with said rotor, an annular tool replacably received about said pilot and against said shoulder, means for holding said tool in driving relationship against said shoulder, an eccentric to rotatably t said pilot, said eccentric having a cylindrical surface eccentric with respect to the axis' of said pilot and adapted to rotatably t said bore, and means for rotating said eccentric.

8. A device for dressing an annular seat on a housing perpendicular to and generally concentric with a bore insaid housing, comprising a head rotatable about a xed axis, an annular tool replacably received on the end of said head and providing a work-surface perpendicular 'to said axis, means for holding said tool in driving relationship on said head, an eccentric having a pilot coaxial with its axis of leccentricity and having a cylindrical outer surface adapted to rotatably iit said bore, said head having an axial bore toreceive said pilot, and means for rotating said eccen? tric.

9. A device for dressing an annular seat on a housing perpendicular to and generally concentric with a bore in said housing, comprising a head rotatable at dressing speed, a dressing face carried by head and disposed radially with respect to the axis of head rotation, a pilot coaxial with said head, an eccentric positioned by said pilot with its axis of eccentricity alined with said axis of rotation, said eccentric having a cylindrical outer surface to rotatably t said bore whereby to position said housing with said annular seat in position for dressing against said face, and

*means to rotate said eccentric to cause relative revolution between the bore axis and the common axis of said pilot and'head.

' GALEN A. BARNES. 

